532 J. W. BEW8. 



The description given by Cockayne and Laing of Tussock 

 Steppe in New Zealand would apply fairly accurately to the 

 mountain veld of Natal : " Seen from a distance, Tussock 

 Steppe appears as a smooth brown carpet on the dimpled 

 hillside. A closer view dispels the illusion, and reveals the 

 bunched-up grass culms and leaves close together at the 

 round base of the tussock, but spreading above and mostly 

 dead at the apices, growing side by side, each some 40 cm. 

 tall, in some places their leaves intermingling and in others 

 distant, and with partially covered and more or less eroded 

 ground between the clumps." Cf. also Yolkens' description 

 of the Alpine steppe formation on Kilimanjai'o as quoted by 

 Schimper.i 



(b) The growth-forms of the Alpine grasses are usually of 

 a more xerophytic type. The lowest leaf-sheaths are very 

 firm, rigid, and persistent. The character and position of the 

 innovation shoots are of importance in this connection also. 

 If these are intravaginal, they are protected by the close 

 sheathing, firm and (persistent nature of the leaf-bases. If 

 they are extravaginal, they are protected by being buried in 

 the upper layers of soil. The more protected species have 

 the advantage, under the more unfavourable climatic con- 

 ditions. In the Midlands, however, the less protected species 

 have the advantage of^quicker growth, greater vigour, and 

 quicker assimilation, and under natural conditions gain 

 dominance. 



It is only through the [artificial influence of fire — particu- 

 larly too early burning — that this is turned to their dis- 

 advantage, their development being too much hastened so as 

 to take place even in winter, when they suffer from frosts. 

 Thus the more protected, tufted, wiry Aristida is ousting 

 the Anthistiria even at lower altitudes. Burning the grass, 

 therefore, seems to have aji ecological effect similar to that of 

 the adverse factors at high altitudes. 



1 Schimper, A. F. W.. • Plant Geography,' English translation, p. 738^ 

 Oxford. 1903. 



